You can also use software to count birds, https://blog.simos.info/how-to-count-the-population-of-flocks-of-birds-using-software/ https://blog.simos.info/how-to-

You can also use software to count birds, https://blog.simos.info/how-to-count-the-population-of-flocks-of-birds-using-software/ https://blog.simos.info/how-to-count-the-population-of-flock... (disclaimer: I wrote the tutorial from a post I found on the Internet. That source post is now gone)